3144960

Appears in sequences

• Order of n-th stable homotopy group of spheres.at n=22A048648
• If X_1,...,X_n is a partition of a 2n-set X into 2-blocks then a(n) is equal to the number of 5-subsets of X containing none of X_i, (i=1,...n).at n=23A130811
• a(n) = A002952(n) + A002953(n).at n=26A180277
• a(n) = n! * (prime(n+1) + prime(n)) / (prime(n+1) - prime(n)).at n=8A204676
• Array read by antidiagonals: a(i,j) is the number of ways of labeling a tableau of shape (i,1^j) with the integers 1, 2, ... i+j-2 (each label being used once) such that the first row is decreasing, and the first column has m-1 labels.at n=47A226167
• Triangle read by rows. T(n, k) = ((2*n)! * k!) / (n + k)!.at n=39A357013
• Triangle read by rows: T(n,k) is the number of simple graphs on n labeled nodes with k articulation vertices, (0 <= k <= n).at n=51A370065
• E.g.f. A(x) satisfies A(x) = exp(x^3 * (1+x)^2 * A(x)).at n=9A389787